diff --git a/src/cmd/6g/align.c b/src/cmd/6g/align.c
index cab2a93c11..31f06b0f7c 100644
--- a/src/cmd/6g/align.c
+++ b/src/cmd/6g/align.c
@@ -102,10 +102,10 @@ dowidth(Type *t)
 {
 	uint32 w;
 
-	w = 0;
 	if(t == T)
 		return;
 
+	w = 0;
 	switch(t->etype) {
 	default:
 		fatal("dowidth: unknown type: %E", t->etype);
@@ -123,13 +123,13 @@ dowidth(Type *t)
 	case TINT32:
 	case TUINT32:
 	case TFLOAT32:
-	case TPTR32:
+	case TPTR32:		// note lack of recursion
 		w = 4;
 		break;
 	case TINT64:
 	case TUINT64:
 	case TFLOAT64:
-	case TPTR64:
+	case TPTR64:		// note lack of recursion
 		w = 8;
 		break;
 	case TFLOAT80:
@@ -158,12 +158,9 @@ dowidth(Type *t)
 		w = wptr;
 		break;
 	case TARRAY:
-		if(t->bound < 0)
-			fatal("width of a dynamic array");
-		if(t->type == T)
-			break;
 		dowidth(t->type);
-		w = t->bound * t->type->width;
+		if(t->bound >= 0 && t->type != T)
+			w = t->bound * t->type->width;
 		break;
 
 	case TSTRUCT:
diff --git a/src/cmd/gc/go.y b/src/cmd/gc/go.y
index a59ab80116..aa8c16df3c 100644
--- a/src/cmd/gc/go.y
+++ b/src/cmd/gc/go.y
@@ -943,6 +943,7 @@ Atype:
 |	Afntypeh
 |	'*' Atype
 	{
+		dowidth($2);
 		$$ = ptrto($2);
 	}
 
@@ -966,6 +967,7 @@ Btype:
 |	Bfntypeh
 |	'*' Btype
 	{
+		dowidth($2);
 		$$ = ptrto($2);
 	}
 |	'*' lname
diff --git a/src/lib/math/pow.go b/src/lib/math/pow.go
index ad7de595ed..8adb72132a 100644
--- a/src/lib/math/pow.go
+++ b/src/lib/math/pow.go
@@ -29,7 +29,7 @@ pow(arg1,arg2 float64) float64
 
 		temp = floor(arg2);
 		if temp != arg2 {
-			panic sys.NaN();
+			panic(sys.NaN());
 		}
 
 		l = long(temp);
diff --git a/src/lib/math/sqrt.go b/src/lib/math/sqrt.go
index 8fe6ef2f01..76b499e880 100644
--- a/src/lib/math/sqrt.go
+++ b/src/lib/math/sqrt.go
@@ -49,9 +49,11 @@ sqrt(arg float64) float64
 		exp = exp + 60;
 	}
 	if exp >= 0 {
-		temp = temp * float64(1 << (exp/2));
+		exp = 1 << uint(exp/2);
+		temp = temp * float64(exp);
 	} else {
-		temp = temp / float64(1 << (-exp/2));
+		exp = 1 << uint(-exp/2);
+		temp = temp / float64(exp);
 	}
 
 	for i=0; i<=4; i=i+1 {
diff --git a/src/lib/math/tan.go b/src/lib/math/tan.go
index 5d9d5685a7..9def4d9cf3 100644
--- a/src/lib/math/tan.go
+++ b/src/lib/math/tan.go
@@ -60,7 +60,7 @@ tan(arg float64) float64
 
 	if flag {
 		if(temp == 0) {
-			panic sys.NaN();
+			panic(sys.NaN());
 		}
 		temp = 1/temp;
 	}